The present paper discusses the key role of creativity as a form of engagement and categorisation in interaction. One decisive way to display engagement ‘at talk’ is when speakers resonate (cf. Du Bois 2014) with what they heard from one another. Speakers constantly imitate, re-use and creatively recombine the utterances and the behaviours of their interlocutors. Recombinant creativity (RC) is a cognitive mechanism that underpins speakers’ formal re-elaboration of utterances and illocutionary forces of others, but also, more generally, the creative intervention on observed patterns of behaviour in context. RC is crucial for primarily two pragmatic and conceptual mechanisms: relevance acknowledgement and schematic categorisation. A persistent tendency towards the proactive reformulation of an interlocutor’s speech is a symbolic and textual indicator of relevance acknowledgement. This is because what is said by the other speaker is overtly put on record and treated as useful information for the continuation of the interaction. The opposite trend – to be measured on a large scale – is an indicator of lack of engagement. RC is also decisive for speakers’ interactional enactment of constructional and socio-pragmatic schemas and the generalisation of form and meaning as a process of shared categorisation.